It is an incredible privilege to take care of children at their most critical juncture. As pediatric critical care practitioners we must be able to provide timely and evidenced based care for these children, and support families with the knowledge that one's chosen treatment is based upon evidence and experience. However, as a specialty we can only create evidence based standards through rigorous clinical research. Committed to a career in intensive care medicine, it is my duty to provide my patients with the highest, evidence based care, and help our specialty grow by conducting studies to gather evidence for the best practices. To do this, I must learn the necessary skills to foster my development into a thorough and rigorous clinical researcher. While I have undergraduate and graduate level experience in statistics and clinical investigation, with the rarity of pediatric disease, multi-ite studies are needed to draw meaningful conclusions about critically ill children. This is particularly important for mechanically ventilated children-the most common yet most variable intervention in pediatric critical care. Seeking to conduct multi-center mechanical ventilation trials, I must equip myself with knowledge and skills about the design and implementation of such trials, and also gain expertise on evaluating potential objective outcomes for trials on ventilated children. The specific research project detailed in this application is the first step fr me to develop these skills. Using an animal model to validate a minimally invasive measure of upper airway obstruction and subsequently applying this measure to mechanically ventilated children at a single site, I hope to master skills related to the evaluation of pulmonary function, particularly upper airway obstruction. Upper airway obstruction is a complicating factor in ventilation trials because it prolongs length of mechanical ventilation. It is a bigger problem in children (compared to adults) as it is estimated on clinical grounds that 1/3 of all pediatric extubation failures result from upper airway obstruction. However, risk factors for and therapies targeting post-extubation airway obstruction are inconsistent, likely because clinical acumen to measure upper airway obstruction is lacking. Therefore, this project describes validating a minimally invasive technique to measure upper airway obstruction, initially in Rhesus Monkeys. It will then be applied in children to evaluate the accuracy of clinical stridor scales, and determine whether commonly applied therapeutics or supportive care impact resolution of airway obstruction, by demonstrating improvement in the objective, non-invasive measures. While this study will equip me with important skills to conduct clinical trials, I will get specifi experience with the nuances of multi-institutional trials through a series of meetings and activities with the NICHD Collaborative Pediatric Critical Care Research Network (CPCCRN) and the Pediatric Acute Lung Injury and Sepsis Investigators (PALISI) Network. These networks have undertaken many multi-center trials in critically ill children, and will help me learn the necessary skills to take a multi-center trial from an idea to reality.